Development of a Ceramic Exhaust Port Liner

A numerical study was performed to rank candidate thermally insulating ceramics by their ability to withstand metal casting processes. The models used to simulate the casting process are generic and can, therefore be used for evaluation of materials for either exhaust port or manifold liner applications. The analysis revealed two materials that would theoretically survive casting, aluminum titanate (Al₂ TiO₅) and zirconia (ZrO₂). Of these, aluminum titanate does not exhibit the low temperature degradation problems generally experienced with zirconia and, therefore, was selected as the material to develop for insulation of the exhaust system.